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Galileo FS-102 Catadioptric Newtonian

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In the interest of full disclosure I have no financial stake in any of the companies listed in the following article.

Galileo is a smaller telescope company that sells quirky, lower-end telescopes and accessories though Apogee Inc, Fry’s Electronics and (occasionally) department stores. While their MSRP list prices on the company’s website are excessive for the products they sell, their products can frequently be found for lower prices in “closeout” situations or from certain discount stores. Recently I obtained a 4” altazimuth-mounted Galileo “Catadioptric Newtonian” for the price of $25 from a “Savers” thrift store. The scope was in excellent condition with the exception of 2 missing screws in the primary mirror cell (both of which were easily replaced). There was still one of the original included eyepieces and included 3x Barlow in the focuser. There was no finder, but there was a dovetail rail for mounting a typical “red dot” finder. I already had a spare red dot sight, so I mounted it, collimated everything, and gave it a thorough test.

The Optics:

The “Catadioptric Newtonian” design is essentially a fast Newtonian with a spherical mirror utilizing a slightly modified Barlow lens built into the focuser that corrects for spherical aberration. This optical design is more correctly called a “Jones-Bird” telescope. Most Jones-Bird telescopes I’ve used have mediocre to poor optics, so I was pleasantly surprised by the optics of the FS-102. The star test revealed very good correction, no discernible astigmatism and no sign of pinched optics. The integrated Barlow lens imparts a very small amount of chromatic aberration, but not enough to be objectionable. The images provided by the scope are surprisingly sharp. Cloud belts on Jupiter were nice and contrasty, and lunar detail was very sharp. There were also good views of M31 (with the dust lane easily visible with averted vision) and the “donut hole” in M57 was visible as well. Not bad for a 4 inch scope!


The included 3x Barlow and 20mm eyepiece (of indeterminate type) were of mediocre quality. They utilized mostly plastic construction and they eyepiece was not threaded for filters. I would recommend anybody who has one of these telescopes to replace them quickly with higher quality accessories. The telescope is typically equipped with a “Mars Eye” red dot finder. The Mars Eye, while very inexpensive, is a very good finder for the price and very easy to use.

Mount & Tripod:

The mount is a peculiar counterweighted altazimuth mount with two counterweight shafts extending downward at angles to each side of the tube. It is certainly an unusual setup. The mount itself is largely made of plastic, but is reasonably stable. The mount is equipped with slow-motion controls on each axis, which is a nice feature. There is a small circular bubble level on the mounting. The tripod itself is tubular metal, although the legs are skinny and the tripod has a slightly too narrow stance. The metal the tube is made out of is fairly thin as well. As such, the tripod can be a bit wobbly. The tripod feet, however, have a nice and unusual feature; they have rubber feet that twist to retract, causing metal spike feet to protrude. Strongly tightening down all joints in the tripod, hanging a weight from the spreader/accessory tray and using vibration dampening pads all helped to compensate for the tripod’s faults.

The Bottom Line:

Would I buy a Galileo FS-102 at the typical asking price brand new? Probably not. However, if you can locate a good deal on a used or closeout scope, it definitely makes a good knock-around backup scope. Good optics on an acceptable mount make it a decent backup to a higher-end primary instrument.


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